| Abstract: | At the Cross Cancer Institute in Edmonton, a concurrently controlled, randomized, prospective surgical adjuvant trial involving Dukes' B2 and C colorectal carcinoma and gastric carcinoma (T1-4, No-2, Mo) has been activated for the last two years. To date, a total of 150 patients have been entered into the three arms of the trial (namely control, immunotherapy, and chemoimmunotherapy). Of these, 127 cases are colorectal carcinoma and 28 are gastric cancer. As part of the protocol, serial CEA determinations are obtained in all patients on a regular three-monthly basis. So far, 28 patients have confirmed recurrence (colorectal 20, gastric 8) demonstrated clinically or radiologically. Out of these 28 patients, 25 (89.2%) had CEA greater than 2.5 ng/ml months before actual demonstration of recurrence. However, if one uses a cutoff of 5.0 ng/ml as significant, that is, one standard deviation from the usual accepted value, then 21 out of 28 (75%) had persistent, elevated CEA's months before the recurrence manifested itself clinically or radiologically. The CEA profiles of three representative cases from each arm of the adjuvant trial are included. It is suggested that serial CEA determinations will be an invaluable adjunctive test in following patients in an adjuvant trial setting. |
